title: Polarisation stabilisation of vertical cavity surface emitting lasers by minimally invasive focused electron beam triggered chemistry.
abstract: Local electron triggered reactions of functional surface adsorbates were used as a maskless, dry, and minimally invasive nanolithography concept to stabilize the polarisation of individual vertical cavity surface emitting lasers (VCSELs) on a wafer in a post-processing step. Using a 30 keV focused electron beam of a scanning electron microscope and injecting volatile organo-metallic (CH(3))(2)Au(tfa) molecules, polarisation gratings were directly written on VCSELs by dissociating the surface adsorbed molecules. The electron triggered adsorbate dissociation resulted in electrically conductive Au-C nano-composite material, with gold nanocrystals embedded in a carbonaceous matrix. A resistivity of 2500 µΩcm was measured at a typical composition of 30 at.% Au. This material proved successful in suppressing polarisation switching when deposited as line gratings with a width of 200 nm, a thickness of 50 nm, and a pitch of 500 nm and 1 µm. Refractive index measurements suggest that the optical attenuation by the deposited Au-C material is much lower than by pure Au thus giving a low emission power penalty while keeping the polarisation stable.
authors.affiliation: EMPA, Swiss Federal Laboratories for Materials Science and Technology, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland. Ivo.Utke@empa.ch
authors.forename: Ivo
authors.initials: I
authors.lastname: Utke
authors.forename: Martin G
authors.initials: MG
authors.lastname: Jenke
authors.forename: Christian
authors.initials: C
authors.lastname: Röling
authors.forename: Peter H
authors.initials: PH
authors.lastname: Thiesen
authors.forename: Vladimir
authors.initials: V
authors.lastname: Iakovlev
authors.forename: Alexei
authors.initials: A
authors.lastname: Sirbu
authors.forename: Alexandru
authors.initials: A
authors.lastname: Mereuta
authors.forename: Andrei
authors.initials: A
authors.lastname: Caliman
authors.forename: Eli
authors.initials: E
authors.lastname: Kapon
mesh_terms: D004583:Electrons; D006046:Gold / Q000737:chemistry; D007834:Lasers; D053768:Metal Nanoparticles / Q000737:chemistry; D008855:Microscopy, Electron, Scanning
chemical_list: D006046:Gold